Anteus glass



Patented May 8, 1923.

UNITEDl STATES PATENT OFFICE.

.ToEL c. vvErnssv AND EDGAE D. TILLYEE, or soU'rHDnIDGE, MASSACHUSETTS;SAID TILLYER AssIGNoE 'ro SAID WELLS.

A. AN'mEUs GLASS.

Application ledfnay i3,

To all wilma t may concern.:

Be it known that we, JOEL C. VELLs and EDGAR D. TTLLYER, citizens of theUnited v surface of the lens so that they will be especially valuablefor use in various types of goggles and the like. Y

The main object of our invention is the process of forming a lensparticularly adapted for use in goggles and the like where it issometimes necessary to have the convex surface of the lens withstand acom'- paratively heavy blow with the Vassurance of the fact that thelens will not be shattered Z5 or broken over the contact of the blow andthus protect the eyes of the wearer.

A further object `of our invention is the process of forming a hardenedlens which consists in heating a lens blank to produce this convexsurface causing vthe same to contract in the cooling of the concavesurface slowly which will tend to exert a pull on the hardened convexsurface'producing a compression in the convex surface and a tension inthe concave surface. A

A further object of the invention is the provision of a lens of theabove characterwhich can be produced at a comparatively provide aneffective protection for-the eyes of the wearer. i

With the above and other objects in view the inventionconsists in thenovel features of construction, the combination and arrange- .ment ofparts hereinafter more fully set forth, pointed out in the claims andshown in the accompanying drawings, in which- F'rgure I is a frontelevation of a pair ofk goggles including, our im ro'ved lens.

. Fi re II is 'a' side e evation of a nonlinished lens' blank.

Figure III is aside elevation of a nished lens blank. ,gf Figure- IV kisa, transverse sectlon of a a convex surface and then suddenly coolinglow cost and which at the same time will Y 1922.A Serial NO.' 560,614. l

heating furnace for producing the concave on the lens.

Figure V isa vertical section illustrating the lens upon the supportingring prior to heating. i

Figure VI is a transverse section showing the lens in a reformedcondition.

Figure VII is a longitudinal sectionA thru a cooling device showing thelens in position for coolino' theconvex surface, and

Figure bVIII is a longitudinal sectional view of la finished lensconstructed in accordance with our improved process.

Referring to the drawings which we have used for illustrating the use ofour improved -lens and the manner of carrying out the process, thenumeral 1A indicates the Xlens framesof a pair of goggles in which thelenses 2 are mounted. The goggles are provided with the usual temples 3for supporting the same upon the face of the wearer,

the lenses illustrated herein being of our improved type. i

The process of forming our improved lens consists inl taking a roughlens blank 4 which is shown in Figure VII for grinding and polishing theopposed surfaces of the` lenses until they are ground down to the proper.thickness :1s-shown in Figure III. It is .preferred to have thesurfaces of the lens I polished prior to hardening as will be set forthhereafter as the hardening of the lens will not destroy .polishedsurfaces..

In Figure III the lens is shown-with` two polished surfaces 5 and 6 andafter a lens has been polished to the required condition it is placedupon a supporting ring 7 having an inwardly inclined bevel portion 8 asillustrated in Figure V.

The ring 7 is preferably arranged within a heating furnace 9 andthelensl arranged within the furnace and mounted upon the upper edge ofthe.ring. The furnace 9 is heated to the required temperature which willsoften the lens and cause the lower Surface thereof ,to drop downwardlyas illustrated in Figure VI, the face of the lens adjacent the edgeresting upon the inclined Surface 8 to thus produce a true arc on theconvex surface of the lens. In order to regulate the required amount oftemperature necessary to cause the lens to drop as shown in FigureVI athermometer lOvis arranged Within the furnace with the upper endprojecting thru thereof f the furnace so that 110 mil/shattered orbroken over the contact .of the the temperature may be readily regulatedby the operator.

After the lens has been heated and formed to the proper shape asillustrated in Figure VI it is quickl transferred to a cooling devicewhich inc udes the supporting plate 11 having a chamber 12 arrangedbeneath the plate in the form of a concave pocket and communicating withthe chamber is an inlet tube 13 which communicates with the interior ofthe chamber 12 to provide a suitable air pressure which is distributedover the convex surface 6 of the lens by means of a plurality ofperforations 14 formed in the late 11 whereby the convex surface of theens will be quickly cooled which will cause the same to contract, setand harden while the upper or concave surface of the lens is in asoftened state.

Attention is called to the fact that when the soft surface on theconcave side of the lens begins to cool it will slowly tend to produce apulling on the hardened convex surface of the lens producing acompression in the convex surface 6 of the lens anda tension in theconcave surface 5 of the lens.

In .Figure VIII the direction of the arrows on the convex surface of thelens illustrates the direction in which the contraction takes placewhile the arrows on the concave surface indicates the expansion of thesoftened selfside of the lens prior to cooling.

From the above it will be apparent that after a lens. has been lut thruthe/above rocess,-the convex sur ace of the lens will in a suilicientlyheated condition to with- -stand comparatively severe blows on thesurface of the lens `without the lens being blow.

In the art of manufacturing glass it is a well known fact that glassunder compression is much stronger than glass under tension and it is,therefore, one of the principal objects of our process to vproducecompres sion upon the convex surface of the lens with a tension in. theconcave surface as it is the convex surface of thelens which mustwithstand any blows.

It will also be apparent that our improved process is comparativelyinexpensive to carry out and at the same time will produce a lens whichwill be extremely effective for the use to which it is to be applied.

We claim:

1. The process of producing protection lenses consisting in heating thelens uniformly and subsequently cooling one face of the lens while theIother is in aplastic condition. l

2. The process of producing a tempered lens consisting in uniformlyheating the lens blank, suddenly cooling one surface thereof, andallowing the opposite surface to cool naturally.

3. The process of producing a tempered lens consisting in finishing thesurfaces of a glass blank, subjecting the parts to heat which will dropthe finished blank to desired curve and suddenly chilling one face ofthe blank to produce a surface tension thereof.

4:. As an article of manufacture a lens blank having opposite inherentstresses on the respective faces thereof.

5. The process of producing a curved protection lens consisting insurfacing the faces f,

of the lens in flat form, subjecting the blanks after surfacing tosuicient heatl to drop the lens to desired curve without 1mpairment ofthe polished surfaces thereof,

and suddenly chilling one face of the blank to produce a surface tensionin the finished blank, increasing the resisting properties thereof.

6. The process of producing a shock resisting ophthalmic lens consistlngin heating the lens to a plastic condition and causing` one face of thelens to harden and set in advance of the other whereby the contractionof the later cooling surface will produce a compression as respects thefirst cooled surface, causing a surface tension effect therein.

JOEL C. WELLS. EDGAR D. TILLYER.

